A feminist media history of quantification, uncovering the stories behind the tools and technologies we use to count, measure, and weigh our lives and realities. Anglo-American culture has used media to measure and quantify lives for centuries. Historical journal entries map the details of everyday life, while death registers put numbers to life's endings. Today we count our daily steps with fitness trackers and quantify births and deaths with digitized data. How are these present-day methods for measuring ourselves similar to those used in the past? In this book, Jacqueline Wernimont presents a new media history of western quantification, uncovering the stories behind the tools and technologies we use to count, measure, and weigh our lives and realities. Numbered Lives is the first book of its kind, a feminist media history that maps connections not only between past and present-day “quantum media” but between media tracking and long-standing systemic inequalities. Wernimont explores the history of the pedometer, mortality statistics, and the census in England and the United States to illuminate the entanglement of Anglo-American quantification with religious, imperial, and patriarchal paradigms. In Anglo-American culture, Wernimont argues, counting life and counting death are sides of the same coin—one that has always been used to render statistics of life and death more valuable to corporate and state organizations. Numbered Lives enumerates our shared media history, helping us understand our digital culture and inheritance.